
def is_prime(n):
    num=10
    if n<2:
        return False
    for i in range(2,int(n**0.5)+1):
        if n%i==0:
            return False
    return True
print(is_prime(13))

# 递归实现阶乘
def factorial(n):
    if n == 1:
        return 1
    else:
        return n * factorial(n - 1)